[Malignant keratoma: Harlequin fetus].

Harlequin fetus, with an incidence of about 1 in 300.000 births, is an extremely severe form of congenital ichtyosis. We report a case of malignant keratoma: a male infant was born at 40 weeks' gestational age. The parents were first cousins. This infant was covered with massive thick, waxy, plate-like scales and deep fissures. There was striking facial distortion including severe eclabium and ectropion. The baby was transferred to the Neonatal Intensive Care Unit but he died at 2 days of age. There is limited information regarding the course and prognosis of neonates affected with Harlequin ichthyosis because most affected patients die within the first days or weeks of life. However, it is now evident that these infants, may have extended survival potential with intensive supportive measures as well as the addition of retinoids. Prenatal diagnosis for malignant keratoma had been performed by fetal skin biopsy and electron microscopic observation at 19-23 weeks estimated gestational age. In 2005, ABCA12 was identified as the causative gene for this disease. It has now become possible to make DNA-based prenatal diagnosis for Harlequin ichthyosis by chorionic villus or amniotic fluid sampling procedures in the earlier stages of pregnancy with a lower risk to fetal health and with a reduced burden on the mothers.